Using 2 maker-rails, some 1/2" aluminum angle and 3D printed parts. We built this leveler for a 3D printer and it seems to work well because while you level to the [print] bed to the hot end. The bed it self can still be slightly off kilter with regards to gravity and this can affect the print. In addition it also seems to dampen the issue of vibration during rapid infills and this has reduced the "catching" of the second extruder on the dual filament printer.